After you remove records using a delete query, you cannot undo the operation. If you want to know which records were deleted, first examine the results of a select query that uses the same criteria, and then run the delete query.

Maintain backup copies of your data at all times. If you delete the wrong records, you can retrieve them from your backup copies.

All records will be deleted.

Suggested Solution no. 3 — Re-install

Warning: please back-up your database before you re-install. This should be done by your software developer (John or Jen).